Initial setup of the Firefox addon

This structure is created by the Firefox addon tool (cfx).
The original files of the extension (script.js, ...) have been moved to
the  directory "data" following Mozilla guidelines
Fixing errors on frontpage

Fixing errors on frontpage due to difference between chrome and Firefox.
Extension can't refer directly in CSS to images provided, so you have to
add a bit of styling in the main.js file
Minor change to packaging script
More bug fixing

Error would show up when clicking the mark all read button on the
frontpage
Bug fixing hide read checkbox

Error would show up when clicking hide read checkbox on the frontpage
Fixing disappearance of "More" link

The "More" link on the frontpage would disappear when clicking "Hide
read", this fix prevents this behavior
Cosmetic changes for the Hide read checkbox

Better alignment of the checkbox with the rest of the header text
Fixing chromism showing on frontpage

innerText property does not exist in Firefox, equivalent is textContent
Fixing a lot of javascript errors

Lots of javascript errors fixed and applying same trick as for the
frontpage for showing the mark all read icon (revision 1cf8ba6)
Fixing error on the comments page when logged out

Node index was hardcoded but it is different whether you are logged in
or not
Bug fixing with local storage on comments page
Bufixing unread comments count on the frontpage

Unread comment count when following a topic was not showing when not
logged in.
Fixed positioning of collapsible comment button

Positioning of the button was not correct in Firefox
Showing parent was not working correctly

Changed the way the parent is displayed (it is now inserted as a normal
table row above the current row)
Cosmetic changes on the comments page

Mostly aligning nicely checkboxes with text